Cognitive Flashcards
The working memory model - description
Baddeley and Hitch (1974) created the working memory model to explain how short term memory is organised and functions. The model consists of four main components: the central executive and three slave-subsystems (the phonological loop, visuo-spatial sketchpad and episodic buffer).
Central executive
An attentional process that has a supervisory role in short term memory. It focuses, divides and switches our limited attention, whilst monitoring incoming data, making decisions and allocating slave-subsystems tasks. It has a limited processing capacity and does not store information
Phonological loop
A slave-subsystem dealing with auditory information, it encodes information acoustically and preserves its initial order. It is subdivided into the phonological store, which stores auditory information, and the articulatory control centre, which allows maintenance rehearsal in order to keep them in the phonological store when they are needed, its capacity is believed to be equivalent to two seconds of speech.
Visuo-spatial sketchpad
A slave-subsystem that deals with visual and spatial information. Logie (1995) subdivided the visuo-spatial sketchpad into the visual cache, which stores visual data, and the inner scribe, which records the arrangement of objects in a visual field allowing the rehearsal of visual/spatial information.
Episodic buffer
A slave-subsystem that was added to the model in 2000. It is a temporary store that integrates the acoustic, visual and spatial information processed by other subsystems. It also maintains a sense of time sequencing and combines this information with long term memory.
Working memory model - strengths
Dual task studies
Application to understanding amnesia
Working memory model - weaknesses
Lack of clarity of central executive - ‘the central executive is the most important but least understood element’ Baddeley (2003), it needs to be more clearly specified than simply as attention
Not a complete explanation of memory - it does not include any explanation of long-term memory or how the memory is encoded and retrieved
Dual task studies - Baddeley (1975)
Found that when participants performed a visual and verbal task together performance on each was no worse than when they were carried out separately. On the other hand when two visual or verbal tasks were performed together performance on both was considerably worse, this is because they both compete for the same slave-subsystem. Therefore it supports the working memory model as it shows that short-term memory is split into separate slave-subsystems.
Multi-store memory model
Atkinson and Shiffrin (1968). It describes the encoding, storage and retrieval of information in to the sensory register, short and long term memory
Sensory register
All stimuli from the environment pass into the sensory register (one store for each sense). The duration is between 0.2 and 0.5 seconds and they have a high capacity. Attention transfers this information into the STM.
Short-term memory store (STM)
Temporary memory store
Capacity - 7 plus or minus 2 chunks (Miller 1956)
Encoding - acoustically (Baddeley 1966)
Duration - 18-30 seconds (Peterson and Peterson 1959)
The duration can be extended through maintenance rehearsal and if rehearsed long enough it will pass into the LTM
Long-term memory store (LTM)
Potentially permanent memory store
Capacity - unlimited
Encoding - semantic (Baddeley 1966)
Duration - unlimited
For information to be recalled it has to be retrieved from the LTM to the STM
Multi-store memory model - strengths
Baddeley (1966)
HM
Application to improving memory - the capacity of the STM can be improved by chunking, fifteen letters could be remembered if they are in groups of three
Baddeley (1966 a,b)
Shows that the STM and LTM are different stores. We tend to mix up similar sounding words in our STM and similar meaning words when we use our LTM, supporting that encoding is different so it cannot be the same store
HM - multi-store memory model
HM had an operation on his hippocampus, severely affecting his memory. He was able to create new short term memories, however he was unable to create new long term ones. This shows that the LTM and STM must be separate stores as one can be damaged whilst the other isnt
Multi-store memory model - weaknesses
More than one type of STM - the working memory model suggests that there a multiple stores that make up the STM (the phonological loop and visuo-spatial sketchpad)
KF
KF was involved in a motorcycle accident, affecting their memory. Their digit span was very poor when the words were read aloud but improved when he read the digits. This shows that there must be two separate components of short term memory.
Tulving (1972)
Split long term memory into two separate components: episodic and semantic.
Episodic memory
Our ability to recall events from our lives.
Episodic memories - features
Time-stamped
Autobiographical
Several interwoven elements
Time travel (can relive them in our minds)
Semantic memory
Our knowledge of the world, including facts.
Semantic memory - features
Not time-stamped
Knowledge of language
Less personal
Tulving (1972) - strengths
HM
Application to improving memory - Belleville et al (2006)
HM - Tulving (1972)
Difficulty recalling memories from his past (episodic) yet his semantic memory was relatively unharmed.
Belleville et al (2006)
Worked with older people that had a mild memory impairment, undertaking a training programme to improve their episodic memory. Improved.
Tulving (1972) - weaknesses
HM - non generalisable, lack of control over variables (memory before damage)
Stores overlap - Tulving (2002)
Tulving (2002)
Views episodic memory as a specialised sub category of semantic memory, found that you can have a fully functioning semantic memory with a damaged episodic one but not the other way around.
Reconstructive memory
Memories are reconstructions and not reproductions. They are stored in fragments and only re-assembled into a meaningful whole upon retrieval. However some fragments are distorted or missing.
Schema theory
Schemas are mental structures that contain our stored knowledge of aspects of the world. When we come across new knowledge the relevant schema is activated and we assume that the new knowledge matches our schema for the scenario.
Reconstructive memory - schema theory
New knowledge that conflicts with an existing schema may not be encoded.
Schemas replace the missing fragments upon retrieval and may distort the recalled ones
War of the ghosts study
Bartlett showed his British participants an unfamiliar native American story, asking them to reproduce it 15 minutes later. This was showed to a new person and they were asked to do the same thing. Found that it became distorted over time with unfamiliar words likely to be replaced by familiar e.g. canoe for boat
Reconstructive memory - strengths
Bartlett’s war of the ghosts study
Application to EWT
Reconstructive memory - weaknesses
Bartlett’s research lacked reliability, no rigorously controlled methods (standardised procedure)
Some memories are remembered accurately
Baddeley (1966b) - aim
To see whether long term memory is encoded acoustically or semantically.
Baddeley (1966b) - procedure
75 participants (from army), independent groups design, hearing test given before study
Four lists of ten words ((A,B,C,D) acoustically similar and dissimilar and semantically similar and dissimilar), read aloud one word every three seconds, 40 seconds to recall in the correct order. Twenty minutes on unrelated tasks, then recall words again in correct order
Baddeley (1966b) - findings
Performance measured through number of words correctly recalled in order, list A lower than list B. No significant difference in C and D after twenty minutes, B showed significant forgetting.
Baddeley (1966b) - conclusion
Findings were ‘puzzling’, suggests LTM encoded acoustically .Some aspect of the procedure must hid the true encoding of the LTM, carried out a further two studies.
Baddeley (1966b) - strengths
High internal validity - well controlled procedure (words matched in lists based on frequency used, one word read aloud every three seconds)
Application to learning to learn - more effective to learn the meaning of things (LTM encoding is semantic)
Baddeley (1966b) - weaknesses
Low external validity - Tightly controlled, dissimilar to real life (ungeneralizable), may actually interact how he found but viewed it as a confounding variable
Confounding variables - procedure does not rule out influence of STM on LTM.
Sebastian and Hernandez-Gil (2012) - aim
Investigate the development of the phonological loop
Sebastian and Hernandez-Gil (2012) - procedure
575 participants from schools in Madrid, 5-17 years, non repeated a year or any cognitive impairments, tested individually during break times, practise sequence given
Sequences of random digits, increasing one at a time and read aloud, asked to recall in order
Digit span was longest sequence they could recall two out of three times without error
Sebastian and Hernandez-Gil (2012) - findings
Clear increase in digit span with age. Significant from 5-11 (mean 3.76-5.28) then slowed to 17 (mean 5.91).
Compared to findings from an earlier study on elderly English patients (digit span for healthy higher than that of 5-6 but similar to those older)
Sebastian and Hernandez-Gil (2012) - conclusion
Compared findings to Gathercole and Alloway (2008). Spanish increase to 17, English to 15 and Spanish lower at each age. Potentially due to longer word length and limited capacity of the phonological loop
Sebastian and Hernandez-Gil (2012) - strengths
High internal validity - controlled variables with a standardised procedure (read aloud at constant rate of one per second)
Application to understanding cognitive abilities - lower digit span can be linked with learning disorders such as dyslexia
Sebastian and Hernandez-Gil (2012) - weaknesses
Lacked some controls - children not directly tested for impairments based on children or parents divulging information
Ungeneralizable sample - all from Madrid
